Practical Considerations for Antibodies in Myeloma

Consensus Guidelines and Recommendations for The CD38 Monoclonal Antibody-based Quadruplet Therapy and Management in Clinical Practice for Newly Diagnosed Multiple Myeloma: From the Pan-Pacific Multiple Myeloma Working Group

The therapeutic outcomes of clinical trials for incorporating anti-CD38 monoclonal antibodies (including isatuximab and daratumumab) into the bortezomib/lenalidomide/dexamethasone (VRd) triplet therapy backbone as the first-line treatment for newly diagnosed multiple myeloma (NDMM) have demonstrated significant improved efficacies. From a safety perspective, the addition of anti-CD38 monoclonal antibodies into the triplet therapies did not raise additional safety concerns. Based on the promising results, the National Comprehensive Cancer Network (NCCN) Guidelines Version 1.2025 had updated the quadruplet therapy incorporating anti-CD38 monoclonal antibodies with VRd-based therapies as the primary therapy for both transplantation-eligible and transplantation-ineligible NDMM patients. Thus, a panel of experts in hematology and oncology with extensive experience in the treatment of NDMM was convened in 2024 to develop consensus recommendations based on recent evidence from pivotal clinical trials and real-world practices, providing clear guidance for optimizing treatment strategies in both transplantation-eligible and transplantation-ineligible patients. The main topics identified for discussion and recommendation were: (i) the benefits and indications for quadruplet therapy for NDMM; (ii) the optimization of quadruplet therapy strategies; (iii) the management and monitoring of potential adverse events for quadruplet therapy, and (iv) the impact of quadruplet regimens on tandem stem cell transplantation and maintenance treatment. Recommendations were then presented to the entire panel for further discussion and amendment before voting. This manuscript presents the recommendations developed, including findings from the expert panel discussions, consensus recommendations and a summary of evidence supporting each recommendation.

Addition of Elotuzumab to Backbone Treatment Regimens for Multiple Myeloma: An Updated Meta-Analysis of Randomized Clinical Trials

BACKGROUND

The efficacy of elotuzumab, an anti-SLAMF7 monoclonal antibody, in treating relapsed/refractory multiple myeloma (RRMM) and newly-diagnosed multiple myeloma (NDMM) has varied in randomized controlled trials (RCTs). Moreover, there is limited data on its real-world application.

PATIENTS AND METHODS

We conducted a systematic review and meta-analysis of RCTs investigating the addition of elotuzumab to backbone antimyeloma regimens. The primary outcome of interest was progression-free survival (PFS). Secondary efficacy outcomes included overall survival (OS), overall response rate (ORR), and rates of very good partial response or better (VGPR). Key toxicities were also evaluated.

RESULTS

Three RRMM trials (n = 915) and 5 NDMM trials (n = 1790) were included, with 50% of the 2705 patients receiving elotuzumab-containing triplets or quadruplets. In RRMM settings, elotuzumab use significantly improved PFS (hazard ratio [HR], 0.70; 95% confidence interval [CI], 0.60-0.82; P < .001; I² = 0%). This benefit was consistent among patients with high-risk cytogenetics (HR, 0.62; 95% CI, 0.43-0.90; P = .01; I² = 0%) and was particularly evident in those previously treated with proteasome inhibitors (PIs) or immunomodulatory drugs (IMiDs). The RRMM cohort also demonstrated better OS, ORR, and ≥VGPR rate. However, the NDMM cohort showed no significant improvements in any efficacy outcomes. Despite an increase in severe (grade ≥3) infections, elotuzumab use did not adversely affect rates of severe cytopenias, severe cardiac disorders, or second primary malignancies.

CONCLUSION

Our results suggest that elotuzumab-containing regimens represent valuable therapeutic options for PI/IMiD-exposed patients with RRMM. In contrast, elotuzumab's role in frontline settings remains limited.

Management of Adverse Events Associated with Pomalidomide-Based Combinations in Patients with Relapsed/Refractory Multiple Myeloma

Multi-agent regimens incorporating immunomodulatory (IMiD®) agents such as thalidomide, lenalidomide, and pomalidomide have become the preferred standard of care for the treatment of patients with multiple myeloma (MM), resulting in improved survival outcomes. Currently, there are three IMiD agents approved for the treatment of MM: thalidomide, lenalidomide, and pomalidomide. Lenalidomide is commonly used to treat patients with newly diagnosed MM and as maintenance therapy following stem cell transplant or after disease relapse. Pomalidomide, the focus of this review, is approved in patients with relapsed/refractory MM (RRMM). Despite survival benefits, IMiD agents each have different safety profiles requiring consideration both prior to starting therapy and during treatment. Adverse event (AE) management is essential, not only to ensure treatment adherence and thus ensure optimal efficacy but also to maintain patient quality of life. Here, we discuss AEs associated with pomalidomide and present five clinically relevant hypothetical case studies in patients with RRMM to provide scenario-driven guidance regarding treatment selection and AE prevention and management in the clinical setting. Lastly, as new treatment approaches continue to be explored in MM, we also discuss novel cereblon E3 ligase modulator (CELMoD™) agents including iberdomide (CC-220) and mezigdomide (CC-92480).

Expert Consensus on the Incorporation of Anti-CD38 Monoclonal Antibody Therapy Into the Management of Newly Diagnosed Multiple Myeloma

INTRODUCTION

Multiple myeloma is a hematologic malignancy that is typically associated with recurrent relapses. There are numerous frontline treatment regimens that are highly effective for individual patients. The introduction of anti-CD38 monoclonal antibody therapy has shifted treatment decision-making in this setting, with many centers now considering the use of daratumumab as part of initial therapy regardless of patient eligibility for autologous stem cell transplantation (ASCT). Daratumumab has demonstrated clinical efficacy and acceptable toxicity in the first and later lines of therapy, increasing complexity in treatment selection and sequencing. Although daratumumab-containing regimens may not be appropriate for every patient, it is increasingly recognized that the most effective regimens should be used upfront, as high rates of attrition mean that many patients in real-world practice may see a limited number of lines of therapy.

METHODS

A panel of experts in multiple myeloma was convened to consider current evidence and treatment practices to inform a series of consensus statements on the optimal management of newly diagnosed multiple myeloma, including not only treatment selection, but the need for infection prophylaxis, route of administration, and mitigation of potential infusion-related reactions, among other clinical challenges.

RESULTS/CONCLUSIONS

The goal of the present review article is to encapsulate these consensus statements and the rationale for their development, which altogether may help inform treatment selection and clinical decision-making in the front line.

Harnessing the Immune System Against Multiple Myeloma: Challenges and Opportunities

Multiple myeloma (MM) is an incurable malignancy of plasma cells that grow within a permissive bone marrow microenvironment (BMM). The bone marrow milieu supports the malignant transformation both by promoting uncontrolled proliferation and resistance to cell death in MM cells, and by hampering the immune response against the tumor clone. Hence, it is expected that restoring host anti-MM immunity may provide therapeutic benefit for MM patients. Already several immunotherapeutic approaches have shown promising results in the clinical setting. In this review, we outline recent findings demonstrating the potential advantages of targeting the immunosuppressive bone marrow niche to restore effective anti-MM immunity. We discuss different approaches aiming to boost the effector function of T cells and/or exploit innate or adaptive immunity, and highlight novel therapeutic opportunities to increase the immunogenicity of the MM clone. We also discuss the main challenges that hamper the efficacy of immune-based approaches, including intrinsic resistance of MM cells to activated immune-effectors, as well as the protective role of the immune-suppressive and inflammatory bone marrow milieu. Targeting mechanisms to convert the immunologically “cold” to “hot” MM BMM may induce durable immune responses, which in turn may result in long-lasting clinical benefit, even in patient subgroups with high-risk features and poor survival.

The Society for Immunotherapy of Cancer consensus statement on immunotherapy for the treatment of multiple myeloma

Outcomes in multiple myeloma (MM) have improved dramatically in the last two decades with the advent of novel therapies including immunomodulatory agents (IMiDs), proteasome inhibitors and monoclonal antibodies. In recent years, immunotherapy for the treatment of MM has advanced rapidly, with the approval of new targeted agents and monoclonal antibodies directed against myeloma cell-surface antigens, as well as maturing data from late stage trials of chimeric antigen receptor CAR T cells. Therapies that engage the immune system to treat myeloma offer significant clinical benefits with durable responses and manageable toxicity profiles, however, the appropriate use of these immunotherapy agents can present unique challenges for practicing physicians. Therefore, the Society for Immunotherapy of Cancer convened an expert panel, which met to consider the current role of approved and emerging immunotherapy agents in MM and provide guidance to the oncology community by developing consensus recommendations. As immunotherapy evolves as a therapeutic option for the treatment of MM, these guidelines will be updated.

How to Train Your T Cells: Overcoming Immune Dysfunction in Multiple Myeloma

The progression of multiple myeloma, a hematologic malignancy characterized by unregulated plasma cell growth, is associated with increasing innate and adaptive immune system dysfunction, notably in the T-cell repertoire. Although treatment advances in multiple myeloma have led to deeper and more durable clinical responses, the disease remains incurable for most patients. Therapeutic strategies aimed at overcoming the immunosuppressive tumor microenvironment and activating the host immune system have recently shown promise in multiple myeloma, particularly in the relapsed and/or refractory disease setting. As the efficacy of T-cell-dependent immuno-oncology therapy is likely affected by the health of the endogenous T-cell repertoire, these therapies may also provide benefit in alternate treatment settings (e.g., precursor disease; after stem cell transplantation). This review describes T-cell-associated changes during the evolution of multiple myeloma and provides an overview of T-cell-dependent immuno-oncology approaches under investigation. Vaccine and checkpoint inhibitor interventions are being explored across the multiple myeloma disease continuum; treatment modalities that redirect patient T cells to elicit an anti-multiple myeloma response, namely, chimeric antigen receptor (CAR) T cells and bispecific antibodies [including BiTE (bispecific T-cell engager) molecules], have been primarily evaluated to date in the relapsed and/or refractory disease setting. CAR T cells and bispecific antibodies/antibody constructs directed against B-cell maturation antigen have generated excitement, with clinical data demonstrating deep responses. An increased understanding of the complex interplay between the immune system and multiple myeloma throughout the disease course will aid in maximizing the potential for T-cell-dependent immuno-oncology strategies in multiple myeloma.

Myeloma: next generation immunotherapy

The course of multiple myeloma (MM) from initial diagnosis to a relapsed/refractory state is characterized by acquisition of drug resistance as well as progressive immunologic dysfunction. Despite this, however, a number of novel therapies that work in part or solely via immune stimulation are in development for MM, with promising early clinical results. Several new whole-cell or multiepitope vaccine approaches are demonstrating immunologic efficacy in smoldering MM or as posttherapy consolidation, with trials ongoing to see whether this translates into delayed progression or elimination of minimal residual disease. Programmed death-1 (PD-1)/programmed death ligand-1 (PD-L1) inhibition in combination with immunomodulatory drugs demonstrated excessive toxicity in randomized trials; however, antibodies targeting PD-1/PD-L1 and other checkpoint molecules continue to be explored in combination with tumor-targeted antibodies and other T cell-directed therapies. B-cell maturation antigen (BCMA) has emerged as the next big antigen target, with multiple BCMA-specific antibody-drug conjugates (ADCs) and T cell-directed bispecific antibodies/bispecific therapeutic engagers (BiTEs) entering the clinic. In initial trials, the ADC GSK2857916 and the BiTE AMG 420 have demonstrated high response rates in relapsed/refractory patients, with depth and durability of responses that may end up rivaling chimeric antigen receptor T-cell therapies. These agents have unique toxicities that require close monitoring, but they are moving forward in larger registration studies and in combination with standard MM agents. Additional ADCs and bispecific antibodies targeting BCMA and other surface antigens (eg, CD38, CD46, CD48, FcRH5, and G protein-coupled receptor, class C group 5 member D) are moving forward in phase 1 trials and may provide even more options for MM patients.

Update on elotuzumab for the treatment of relapsed/refractory multiple myeloma: patients' selection and perspective

Monoclonal antibodies (mAbs) targeting antigens expressed by plasma cells demonstrated major clinical activity in multiple myeloma patients and therefore became a new major class of drug for these patients. Elotuzumab is a humanized mAb targeting the cell surface signaling lymphocytic activation molecule family member 7, a glycoprotein highly expressed on plasma cells, that is the second mAb approved for the treatment of myeloma patients. The mechanism of action of elotuzumab includes natural killer cell (NK) mediated antibody-dependent cellular cytotoxicity and direct activation of NK-cells. Elotuzumab has been approved in combination with lenalidomide and dexamethasone (Elo-Rd) and pomalidomide and dexamethasone (Elo-Pd) for the treatment of relapsed myeloma patients. The present review will focus on elotuzumab, providing a summary of the mechanism of action, efficacy and safety and taking into consideration patients’ selection.